With the improvement of process technology and material in flat panel display, an AMOLED has gradually become a mainstream choice for future display devices.
FIG. 1 shows a conventional AMOLED driving circuit, which comprises a first semiconductor controllable switch T1, a second semiconductor controllable switch T2, an energy storage capacitor C1, and an organic light emitting diode D1. A terminal of the second semiconductor controllable switch T2 is connected to a first controlling voltage VDD, and the other terminal is connected with a positive electrode of the organic light emitting diode D1. A negative electrode of the organic light emitting diode D1 is connected to a second controlling voltage VSS. A source of the first semiconductor controllable switch T1 is connected to a data driving signal SN of the AMOLED display panel, a gate of the first semiconductor controllable switch T1 is connected to a scan driving signal GN of the AMOLED display panel, and a drain of the first semiconductor controllable switch T1 is connected to a gate of the second semiconductor controllable switch T2. The storage capacitor C1 is connected between the gate and source of the second semiconductor controllable switch T2, so that the second semiconductor controllable switch T2 works in a saturation region, thereby providing current to the AMOLED for emitting light.
In order to increase drive consistency of the AMOLED driving circuit, panel manufacturers provide a method using pulse width modulation to drive the AMOLED driving circuit (please refer to CN Patent Application No. 201410014397.X, titled “AMOLED driving circuit and driving method thereof”). By dividing a driving time in one frame of an organic light emitting diode into N sub-frame times, the influence of the storage capacitor C1 applied to the second semiconductor controllable switch T2 can be eliminated, but a transmission speed of a data driving signal at each sub-frame time should be relatively increased, so that the data transmission speed of the AMOLED driving circuit will be restricted by a transmission speed of a driver IC and an access speed of a storage.
Accordingly, it is necessary to provide a method of driving an AMOLED to solve the technical problem in the prior art.